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Viewing particular Mails freezes Thunderbird

Thunderbird Crashing and slow performance
julian46 replied
julian46
julian46

For a few days I'm having trouble with Asana mails (notification mails informing me about replies, comments, etc).

Clicking on the mail to view it freezes Thunderbird for a good 5 seconds while one CPU core spins at 100%. This only happens with Asana mails (or at least I haven't found any other problematic senders).

I guess it's a problem with validation or parsing of the mail's HTML content. But I don't know how to debug this.

I can't pinpoint exactly when it started happening, but it was around the time I've switched to the [new snap release track](https://support.mozilla.org/en-US/kb/channel-choices-thunderbird-snap-and-flatpak#w_snap-channel-changes-in-2026). But since this happens with Snap and Flatpak I think the culprit may be the 153.0 update.

Things I've tried:

  • Clearing cache and msf files.
  • Troubleshooting mode with add-ons disabled.
  • Reinstallation. Creating new profile + importing old data.
  • Switching from Snap to Flatpak
  • Switching Message Body display to Plan Text or Simple HTML.
  • Disabling HW acceleration.
  • Checking console for suspicious output.

Anything I can do to create handle the problem or collect information for a proper bug report?

For a few days I'm having trouble with Asana mails (notification mails informing me about replies, comments, etc). Clicking on the mail to view it freezes Thunderbird for a good 5 seconds while one CPU core spins at 100%. This only happens with Asana mails (or at least I haven't found any other problematic senders). I guess it's a problem with validation or parsing of the mail's HTML content. But I don't know how to debug this. I can't pinpoint exactly when it started happening, but it was around the time I've switched to the [new snap release track](https://support.mozilla.org/en-US/kb/channel-choices-thunderbird-snap-and-flatpak#w_snap-channel-changes-in-2026). But since this happens with Snap and Flatpak I think the culprit may be the 153.0 update. Things I've tried: * Clearing cache and msf files. * Troubleshooting mode with add-ons disabled. * Reinstallation. Creating new profile + importing old data. * Switching from Snap to Flatpak * Switching Message Body display to Plan Text or Simple HTML. * Disabling HW acceleration. * Checking console for suspicious output. Anything I can do to create handle the problem or collect information for a proper bug report?

Modified by julian46

All Replies (2)

Wayne Mery
Wayne Mery
  • Top 25 Contributor
  • Moderator

I've asked Julian to email me a copy of a problem email.

julian46
julian46 صاحب السؤال

I've sent the information.

On that note, I also found out that the freeze does not occur when selecting several of the emails at once. Likely because the messages only show a summary rather than the full contents. See screenshot for what I mean.

اطرح سؤالا

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